Thanks for such a thorough and helpful comment! That is an excellent tip to add to the list. When we lived in our Cityhouse in Ohio (before the move to our homestead), we were warned about the lead content in our area---not in the 100 year old house paint, but the lead content along the street from the decades of leaded gasoline that had traveled up and down the road over the years.
Samuel Thayer also recommends sniffing bulbs, too! All of the allium (onion) family is edible, and the stinky/delicious odor of a garlicky or oniony bulb is a giveaway that it is safe and good to eat.
Welcome to Steemit, by the way! We just followed you. :)